PL-71 turntable speed control deterioration
Over the past couple of years, the speed control circuits on my Pioneer PL-71 direct drive turntable have deteriorated.
This deterioration is manifest in:
1. Some speed instability for a while on start-up.
2. Needing to turn the 33rpm controller up to maximum to achieve a fast enough (normal) speed.
I don't use the TT much in the 2nd system, so it's not a massive issue, but I'd like to sort it while I've got a bit of time over the summer.
I've read on other forums that speed issues with the PL-71 may be due to oxidising of the speed-control micro-switches in the circuit, or possibly the capacitors in the speed control circuits deteriorating over time.
I'm willing to give repair a go, but don't want to mend things that don't need mending.
Any thoughts from the boffins here as to which is the most likely fault, and where I should start my initial pokings about....?